The present invention relates to a resin molding machine and a method of resin molding, more precisely relates to a resin molding machine for molding a work piece on which a plurality of elements, e.g., semiconductor chips, and a method of molding the same with resin.
A conventional method of manufacturing semiconductor devices molded with resin will be explained with reference to FIG. 13. A work piece 12 is a substrate on which a plurality of semiconductor chips 10 are matrically arranged with prescribed separations. An upper side of the substrate 12, on which the semiconductor chips 10 have been mounted, is molded with resin 14. Each semiconductor chip 10 is cut together with a basic material of the substrate 12 and the solidified resin 14, so that a plurality of semiconductor devices can be produced. By the method, many semiconductor chips 10 can be provided on the substrate 12 with high density and molded with the resin 14, so that small semiconductor devices can be efficiently manufactured.
However, in the conventional method, the substrate 12 is molded by potting the resin 14, so it takes a long time to solidify the resin 14. In the case of molding in a molding die, if thickness of the substrate 12 is not even, resin flash is formed, wires are badly moved in the resin and forming voids cannot be prevented.
The present invention was invented to solve the problems of the conventional method.
An object of the present invention is to provide a resin molding machine and a method of resin molding, in each of which a work piece, e.g., a semiconductor wafer, on which a plurality of elements, e.g., semiconductor chips, are arranged, can be securely and efficiently molded.
To achieve the object, the resin molding machine of the present invention comprises:
a lower die on which a work piece to be molded is set;
an upper die clamping the work piece with the lower die;
a clamper being provided to the upper die, the clamper enclosing a resin molding space of the upper die, the clamper being capable of vertically moving in the upper die and always biased downward, wherein a lower end of the clamper is downwardly projected from a resin molding face of the upper die when the lower die and upper die are opened; and
a release film feeding mechanism feeding release film, which is easily peelable from the upper die and resin for molding, so as to cover the resin molding space. Since the work piece is molded with the release film, no resin is stuck on the resin molding face of the die and a molded product can be easily peeled off from the die. The resin molding space is securely sealed by the release film, so the work piece can be securely molded without forming resin flash. Since the work piece is set in the lower die, the work piece can be easily set and preheated.
The resin molding machine may further comprise another release film feeding mechanism feeding release film so as to cover a surface of the lower die on which the work piece is set.
The resin molding machine may further comprise a release film sucking mechanism, which fixes the release film on a lower end face of the clamper by air suction and which fixes the release film on an inner face of the resin molding space, which is constituted by the resin molding face of the upper die and an inner face of the clamper, by sucking air from an ceiling face of the resin molding space.
The release film sucking mechanism may comprise:
a first air-hole being opened in the lower end face of the clamper;
a second air-hole being opened in an inner face of the clamper and communicated to an air path, which communicates the second air-hole to a side face of the upper die; and
an air sucking unit being communicated to the first air-hole and second air-hole for air suction.
In the resin molding machine, the upper die may have a plurality of cavities, which respectively correspond to element portions of the work piece. With this structure, the work piece, on which a plurality of elements, e.g., semiconductor chips, are arranged, can be easily molded.
In the resin molding machine, the lower die may have a plurality of cavities, which respectively correspond to the element portions of the work piece.
In the resin molding machine, the upper die may be capable of moving in the vertical direction and biased toward the lower die.
In the resin molding machine, the lower die further may have an overflow cavity for reservoiring resin overflowed from the resin molding space when the work piece is molded with the resin; and
the clamper may have a resin path communicating the resin molding space to the overflow cavity.
The method of the present invention comprises the steps of:
setting a work piece to be molded on a lower die;
feeding release film, which is easily peelable from the upper die and resin for molding, between an upper die and the work piece so as to cover a resin molding space of the upper die;
clamping the work piece and the release film by the upper die and the lower die; and
molding the work piece with the resin,
wherein a clamper, which is provided to the upper die, which encloses the resin molding space and which is capable of vertically moving and biased downward so as to downwardly projected a lower end of the clamper from a resin molding face of the upper die, contacts the work piece molded so as to seal peripheral of the resin molding space in the clamping step, and
wherein the resin is introduced into the resin molding space while the upper die is gradually moved to the lower die, the movement of the upper die is stopped at a clamping position, then the resin molding space is fully filled with the resin so as to completely mold the work piece.